The immigration overhaul may have died in Congress earlier this year, but a growing number of businesses are adopting one part of it voluntarily. Some 30,000 businesses have now signed onto a federal computer program to check the legal status of new hires, and the Department of Homeland Security says 1,000 more are joining every week.

It's an exponential increase for a system first known as "Basic Pilot." But after running focus groups, DHS now calls it "E-Verify." Critics say the program is rife with errors, and worry its fast expansion will lead to legitimate job applicants being wrongly denied jobs.

Fast System with Shortcomings

A year ago, Fort Myer Construction Company in Washington signed on, hoping to avoid the embarrassment and hassle of an immigration raid as federal authorities increased their efforts. The company has a workforce that is 85 percent Hispanic. Carla Schmidt, a human resources assistant, says she took an hour-long online tutorial to learn how to check applicants' legal status against federal databases and finds the system easy to use.

"As soon as you put in information and click 'submit,' it'll tell you something. Either authorized, not authorized or in process," Schmidt said.

While E-Verify identifies false Social Security numbers, a major shortcoming is that it has not been able to detect legitimate documents that have been stolen. A new system hopes to catch some of that by letting employers compare the photos on certain immigration documents. DHS also wants to negotiate deals with state motor vehicle agencies to include driver's license photos.

Fort Myer's human resources director, Mike Caro, says E-Verify takes away the awkward uncertainty at those times he suspects a job applicant's document may be false.

"We say, 'Okay fine, you say it's legitimate. We're not sure.' So we're going to check you through Homeland Security. And traditionally those people we've questioned, don't return," Caro said.

Challenging the System

Caro says there have been at least a dozen applicants in the past year whom the system did not approve, and when they didn't protest, Caro assumed they were in the U.S. illegally. Fort Myer's project engineer, Rahi Golshan, did dispute his non-confirmation — and was able to prove he had the right to work after all.

"I think I called DHS first and they told me to call Social Security," Golshan says. "Then I took a visit up to Baltimore and went to Social Security office there."

It turned out Golshan's records had not been updated since he became a U.S. citizen. And there are many other cases like Golshan's. Homeland Security officials say they hope to clear them up preemptively. But critics point out there are millions of Social Security records with typos or misspellings. In all, nearly 18 million agency records, or 4 percent, have errors, says Jim Harper, director of information policy studies at the Cato Institute.

"That represents 1 in 25 new hires in the U.S. being told by the federal government, 'You can't work unless you go and get this straightened out.' I don't think big companies realize that," Harper said.

Employer Misuse

Harper believes if E-Verify were mandated nationwide — as some in Congress propose — the resulting flood of fixes would be a human resources nightmare. And there's another concern.

"The problem is that some employers follow the rules and some employers don't," says Tyler Moran, employment policy director of the National Immigration Law Center. She says to avoid racial profiling, employers are only supposed to conduct the check after they hire someone. But one of the government's own studies found 42 percent of businesses did not do that.

"What the employer was trying to do is cover themselves and say, 'You know what, I'm not going to put in the energy filling out this form until I see if there are any problems.' And so they put them through the system as a way of kind of pre-screening them," Moran said.

Moran says because of the high error rates in the Social Security Administration's records, some who can legitimately work will receive a tentative non-confirmation, but they won't have the chance to correct it if the employer never tells them.

Kathy Lotspeich, acting chief of the verification division of U.S. Citizenship and Immigration Services — which oversees E-Verify — says officials are aware of employer misuse.

"We are in the process of standing up a monitoring and compliance unit, where we would be able to follow up with employers that were not using the program properly," Lotspeich said.

Homeland Security has also begun running radio and print ads in Arizona — in English and Spanish — that explain employees have the right to keep working while they contest E-verify's results.

DHS plans a national media campaign early next year to promote E-Verify and it's forging ahead to mandate the program where it can. Federal agencies had to start using it last month and Lotspeich says officials are working on regulations to require federal contractors to use it.